Answer: d
Explanation: An electric arc furnace generates a lot of heat when the working metal comes in contact with the electrode. The heat that is generated in this joining process is of the order 6000°C to 7000°C.

2. The distance from the center of arc to the tip of electrode is called what?
a) Arc distance
b) Arc length
c) Arc crater
d) Arc depthView Answer

Answer: b
Explanation: The distance from the center of the arc to the tip of the electrode, right till the bottom of the crater is defined to be the arc length. The arc length is considered to be one of the most essential variable in welding process.

Answer: d
Explanation: In an arc welding process, there are alternators used for producing high current and function at lower frequency, and there are alternators which are of high quality and work at high frequency. The functioning frequency of these alternators is 400 Hz.

Answer: a
Explanation: Electrodes which are classified into three types, fast fill, fast freeze and fill freeze. Among these, the fast fill electrodes are considered to be able to operate at extremely high welding speeds, and hence fast fill electrodes are designed for quick melting.

Answer: c
Explanation: In an arc welding process, there is a direct conversion of electrical energy into heat energy. An approximate amount of 1 kilo Watt hour of electrical energy gets converted into heat energy for this process.

Answer: b
Explanation: Arc welding machines are able of working on both alternating current supply as well as direct current supply. But mainly arc welding machines work on D.C. supply only, where the positive terminal is connected to the welding machine.

Answer: b
Explanation: Electrodes which are classified into three types, fast fill, fast freeze and fill freeze. In fast freeze electrodes, a filler metal is supplied. This filler element gets solidifies and provides a variety in positions of the weld.

9. Which material is not used as an iron coating on the electrode used in arc welding?
a) Cellulose
b) Iron powder
c) Calcium fluoride
d) SteelView Answer

Answer: d
Explanation: Materials that are used as coating on the electrode, that are used in arc welding, are cellulose, iron powder, calcium fluoride and rutile. Iron is used for ease of weld, but not steel, though it mainly contains iron.

Answer: b
Explanation: During the operation of the arc welding process, the positive pole of the electrode experiences two third of the heat and the negative pole experiences one third the heat, hence the positive pole burns away faster than the negative pole.